Gas scrubbing



Patented .Jan. 16, 1934 l a e Carbideand Carbon Chemicals Corporation, acorporation of New York No Drawing. Application July 29, 1932 Serial No.626,209

7 Claims. (Cl. 23-2) The invention relates to scrubbing of gases portionofthe solution as a means of constant with amine solutions, referringmore specifically control. I find that satisfactory control of foamtothe prevention of foaming in such solutions. ing may be obtained bycontinually filtering and Foaming is commonly encountered in nearlyrecircu at g from t0 0f the total 5 all types of gas scrubbing systems.Where the .culating amine solution in the scrubbing apparascrubbingmedium is Water and the like, it is cus-. tus; and that sudden formationof large amounts tomary to add hydrocarbons, mineral or vegetable 0f0am, as O a y Occurs, ay be disoils, or partially soluble alcohols tostop the foamp t d by d in a m ll t f n mal or ing. These agents'aremoderately successful ex- Vegetable a y about 3 a o s 0f Oil t 10 ceptin certain extreme cases where the foaming each 10,000 gallons of aminesolution will be sufis excessive. When amine solutions, such as fi t t paming temp rar y. Th il t solutions of ethanol amines for example, areused h r with muIa d f am n a nts ar r as scrubbing media the foamproblem is agmoved by the filtration through the activated gravatedinasmuch as these solutions tend cerhcn- 15 t foam seriously when in t tt acid After use for some time the activated carbon gases, Foaming of tabsorbing medium will lose its effectiveness to an appreciableexseriously interrupts normal operation of gas teht- When this Occursthe carbphmey be rescrubbing equipment h usueleenditien eeeur vived orrestored to substantially its original ring i pragtice i an apparentclogging of t effectiveness by usual reactivation methods, such 20ordinary countercurrent gas scrubber which reas treatment Withsuperheated Steam. In pracs its in the formation of a high pressure droptical applications of my invention it will be adthrough the scrubber,frequently accompanied Vantegecus t p v d tWO filtering s, y by 9,1 ofscrubbing1iquid one of which is in use for filtering at any one Inattempting t0 overcome the foaming diftime, SO that there Will always beavailable one 25 ficulties when using amine solution, I have tested unitcontaining fresh carben- This arrangement the effect of the usualhydrocarbons, oils and allows a mass of contaminated carbon to be therdefoaming agents 1 h found t t vege reactivated conveniently withoutinterrupting the table nd i l oil r temporarily effective, circulationand filtration of the amine solution. but do not afford permanentrelief. The use of I claim! 30 these oils prevents foaming for some timeb t 1. Method of treating aqueous solutions used after a certain timefoaming again becomes seriin gas treating Operations and which containous and is not affected by further additions of an amine and which tendto foam wh ch comthis type of agents. Distillation, freezing and prisesbringing at least portion the solufiltration, treatment with varioussolvents and tion into contact With activated o 35 il th of treating tabsorbing medium 2. Method of treating aqueous amine solutions have beentried with no useful or practical reused in gas treating operations andwhich tend sun-Ia to foam which comprises adding an oil to said I havefound that activated carbon is effective Solution and bringing at leasta P ti Of Said in removing th foam-forming agents from solution intocontact with activated carbon.

3 ous amine solutions used in scrubbing acid gases. Mcthod of treating qus ethanol amine By a simple filtration of the contaminated liquidsolutions used in a atin operations and through a bed of activatedcarbon the tendency which have a tendency to foam Which p s s to foam isstrongly suppressed. Various types of adding to the Solution an agentchosen from activated carbons have been tested and found to the groupconsisting of animal a V table 45 be eflecti ve, for example: cocoanutcharcoal, acti- Oils and bringing a least a P t on of said soluvatedwood charcoal, and bone charcoal, in varition into contact with an agentchosen from ous sizes such as 8 to 14 mesh. There are certain the g upconsisting of act vated cocoanut charadvantages in using activated woodcharcoal, incoal, activated wood charcoal, and activated bone asmuch asit permits somewhat easier filtration charcoal.

50 than other available activated carbons. 4. Process of scrubbing acidgases which com- I have also found useful a combination of two prisesbringing the gas into contact with an methods of treating the aminesolutions, namely aqueous solution which contains an amine and additionof vegetable or animal oil to secure imcontinuously bringing a portionof the solution mediate and temporary relief from foaming, and intocontact with activated carbon..

use of filtration through activated carbon of a 5. Process of scrubbingacid gases which com- 1,944,122 prises bringing the gas into contactwith an '1. Process of scrubbing acid gases which comprises bringing thegas into contact with an aqueous solution of ethanol amines, adding tothe solution an agent chosen from the group which consists of animal andvegetable oils, and

continuously filtering at least about 5% oi. the

solution through activated carbon.

HARVEY ROME FIFE. r

CERTIFICATE. or CORRECTION.

Patent No. 1, 944, 122.

January 16,, 1934.

7 It is hereby certified that the-name of the patentee in the abovenumbered patent is' erroneously written and printed as "Harvey RomeFife" whereas said a name should have been written and printed as HarveyRowe Fife; and that the said Letters Patent should be read with thiscorrection therein that the same may conformto the record of the case inthe Patent Office.

, Signed and sealed this 20th day of March, A. D. 11934.

(Seal) F. M. Hopkins Acting Commissioner of Patents.

